Educated at Eton
College and Christ Church, Oxford, he was
appointed a Teller of the Exchequer in 1764, and ten years later was
returned to Parliament as one of the
Members for Buckinghamshire. In the House of Commons he was a sharp critic of
the American policy of Lord North. In September
1779 he succeeded his uncle as Earl Temple; in
1782 was appointed Lord Lieutenant of
Buckinghamshire; and in July of the same year became a member
of the Privy
Council and Lord Lieutenant of Ireland
in the Ministry of Lord Shelburne. On
his advice the Renunciation Act 1783 was passed, which supplemented
the legislative independence granted to Ireland in 1782. By Royal
Warrant he created the Order of St
Patrick in February 1783, with himself as the first Grand
Master. Lord Temple left Ireland in 1783, and again turned his
attention to English politics. He enjoyed the confidence of King George III, and
having opposed Fox'sEast India Bill, he
was authorized by the King to say that "whoever voted for the India
Bill was not only not his friend, but would be considered by him as
an enemy", a message which ensured the defeat of the Bill. He was
appointed a Secretary of State when the younger
Pitt formed his Ministry in
December 1783, but resigned two days later. In December 1784 he was
created Marquess of Buckingham.

In November 1787 he was appointed Lord Lieutenant of Ireland
under Pitt, but his second tenure of this office was hardly as
successful as the first. He was denounced by Grattan for
extravagance; was censured by the Irish Houses of Parliament for
refusing to transmit to England an address calling upon the Prince of Wales to
assume the regency; and he could only maintain his position by
resorting to bribery on a large scale. Having become very unpopular
he resigned his office in September 1789 and subsequently took very
little part in politics, although he spoke in favour of the union
with Ireland. He died at his residence, Stowe in Buckinghamshire, on 11 February 1813,
and was buried at Wotton.

In 1775 he had married Lady Mary Nugent, daughter of the 1st Viscount Clare
(later the 1st Earl Nugent), whom he succeeded as Earl
Nugent in 1788. Lady Buckingham died in 1812.